Magnetic core for electric apparatus.



v W. C. FISH.

MAGNETIC GORE FOR ELECTRIC APPARATUS.

APPLICATION FILED JAN.12. 1907.

952s 1 Paterna@ ma?. i5,

AfA/fw Inventor: Walter C. ish,

W. C'. FISH. MAGNETIC GORE- PoR ELE vMPLICATION FILED GTRIG APPARATUS.

JAN. 12, 1907,.

` Patented Mar. 15, 1910.

2 SHEETS-SHEET 2.

Inventor: Walter` C. V'sh, ,OU M

UNITED sTATns PATENT orricn.

'WALTER CL FISH, or LYNN, MASSACHUSETTS, ASSIGNOR To GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK. I

MAGNETIC CORE FOR ELECTRIC APPARATUS.

Specification Of Letters Patent. Patented Mar. 15, 1910.

Appncrfm ined January 12, i907. 4swarm. 351,968.

To all w/Lom it may concern:

Be it known that I, VALTER C. FISH, a(y citizen ot' the Inited States, residing at Lynn. county ot' Essex, State of Massachusetts. have invented certain new and useful Improvements in Magnetic Cores for Electric .-\`1. ]')aratus, ot which the following is a specieation.

)Iy invention relates to electric apparatus employing laminated magnetic cores, and its ohject is to provide a novel and simple construction tor seci'lring a core of cylindrical form.

The ditiicnlty that has been experienced heretofore in constructing a laminated core of cylindrical t'orm in large sizes has led to the. almost universal use of cores rectangular, or practically rectangular, in crossseetion. With such a core, either the winding must be rectangular to conform to the cross-section of the core, or spaces must be left between the core and the winding. In either case. more copper is required than would have been necessary in a cylindrical winding with a closely fitting cylindrical core.

My invention consists in constructing the core out otl magnetic lamina, each heut in the form ot an involute. 'lhese may he closely packed together to form a core cylindrical in form. I prefer to make the lamina of only such a portion otl the involute curve that when they are packed together, they will not entirely surround the longitudinal axis of the core,-that is to say that the angle suhtended by two planes passing through thisaxis to the inner and the outer edges ot a lamina will he less than 360 degrees. In case a practically solid ctv-e is required, .the core may be constructed ot' a plurality ot superposed concentric cylinders, each composed of laminas of involut-e cross-section.

My invention will best be understood by reference to the accom; anying drawings, in which F ignre 1 shows a plan view of a core constructed in accordance with my invention; Fig. 2 shows a perspective View of one of the. laminar; Figs. 3 and 4 show a core and winding arranged in accordance with my invention, and applied as a reactive coil in an arc lamp: Fig. 5 shows a plan View of a transforme: with closed magnetic circuit arranged in accordance with my invention;

`o' ning of the core.

Fig. 6 Shows a cross-section on the line 6-6 Of Fig. 5; Figs. 7 and 8 show Similar views of a reactive coil with nearly closed magnetic circuit; and Figs. 9 and 10 show perspective views of single laminae for the transformer and reactive coil respectively.

In Fig. l, A1 and Afrepresent two superposed concentric cylinders, each of whichis composed of magnetic lamin stamped in the form of an involute, as shown in Fig. 2. The laminae are closely packed together to produce the cylindrical core of Fig. 1. The purpose of employing two superposed cylinders is to secure a core nearly solid,-that is, a core with a small central Opening. The ratio of the inside to the outside diameter of a cylinder that can be built up from a single set of laminie has a certain minimum value, so that if a central opening. smaller in pro-4 portion to the outer diameter of the core, is required, a plurality of cylinders must be employed in therconstruction yot the core. The laminas in the two cores of Fig. l are shown arranged oppositelyjvith respect to the right or left-hand direction of the invov lute. This is to give greater strength and rigidity to the core.

Since a core constructed in accordance with my invention necessarily has a central opening of appreciable size, unless an excessive number of superposed cylinders are employed in its construction, my invention is particularly advantageous in applications where a passage lthrough the center of the core is desired. For mstance,in Figs. 3 and 4, I have shown my core construction applied to the reactive coil of an arc lamp, which it is desired should surround the carbon rod, in Order to secure a compact construction. My core construction is part-icularly well adaptedto such a purpose, since it provides the central opening required. In these figures B represents the Winding of the reactance coil, which is cylindrical in form, closely ttin the core. C represents the carbon rod w ich-passes through the central The construction of arc lampforms no part of my invention,

Vand need not be described in detail.

In the preceding figures I have shown .a core arranged for a coil with open magnetic circuit. In Figs. 5, 6 and 9 is shown a trans- 'former construction with closed magnetic leo circuit, D representing the core, d and 'd" the individual laminae, and E the transformer le l ainsi rj.- m'e ls-slmped @zich fili. i: than 'the other, :md laminas inner leg longei: are interleaved l i the mile? leg; longer, as

5 P. lamina (.7/ comisllc Ciwui 05j' each lamina r.

, o l l@ moll er modification will .Vl for :i muclivo cnil willi l clozscd magnetic ii'cuit, F represent 10 Vif' f" mi individual lamina, and G 'Tim eifiisruclion will be imioction 0l lli@ di'zxwii filled if l5 .l Cylii'idel fitting flieiiein :is

i fmilians lo lie particular cmisli'ucall modifications Within ille I euliimi. as new and desire to Secure il; glie Unilelil. Stilles, is,- l:a if zq'ipai'ulus, a Cyliilclificnl fixicll'icul inagneic com of lamui each benl; in

the form of :an izivolule nml Only slim-mini ing; n portion o? (im om :1:-'i

En an electric uppamh Winding; and u Cove therefor n if; laminar: a a www, miimi im llw form of suoli. n pOlmicm uf nu iiirolul :15 mil lo enlirely sui'ouiull lli@ lmy filmlimil axis nl' lli@ com: closly packed lo 'im-iii :i @Nimh-i'.

53. lu an alicliiw appzuulim uylimlxiuil Winding, :mil n. iiiaignolir; wie llmi'vlm: vm ppiing u plurality of Supoffpnsml umm-mimicylinders ezu'li '.foi'xipofeml m" lnminm ff inmlute cross-s 4v. In an elemiic appui-alim, linlliilzzzl Windingy and :i nmguelic cove llim'l" r wmpiisingl :L plllz'nllly wi sulmi'pfiscll fnltiziilriv will readily Suggest i mfcxnfdiiigly I do not (lesive cylinde @sich composed olf lzui'iiiin-, mf imilut@ arms-section, l'lw, lmixmzic. m mljaminl l cylinders being oppositely zurangml will, rw .n om" mm to @over m the ap-` spcct lio the fight or Mill-hand clix-@climi nl' die involul'fe.

ln *witness wliercof, l. lmvc hummm my hand This 'ninth (luy of zimmix 

